1. Field of the Invention
The present invention relates to an apparatus and method for measuring the quantity of printing papers used in printing and warning a printing part exchange time using the measured quantity of the printing paper.
2. Description of Related Art
Of apparatuses (e.g., printer, facsimile apparatus or copying machine) having a printing mechanism, some include a warning apparatus which warns a user the time at which printing part such as ink or toner (collectively referred to as ink) should be exchanged or supplied or the time at which printing paper should be supplied.
This kind of ink exchange time warning apparatus generally comprises a printing paper quantity measuring apparatus in which contents memorized in a memory are initialized when an ink ribbon, for example, is exchanged to a new one and the number of printing papers is accumulated and memorized in the memory each time the printing is executed and a warning apparatus for warning a user when the accumulated value memorized in the memory exceeds a predetermined warning reference. If the average number of printing papers assumed to be printable without shortage of ink after the ink ribbon was exchanged to a new one is set to the warning reference, then it is possible to warn the user of the time at which the ink ribbon should be exchanged next.
In order to enable the ink exchange time warning apparatus to function normally, when the ink ribbon is exchanged to the new one, the accumulated value of the number of printing papers should always be initialized. On the other hand, in the maintenance process of the printing mechanism, for example, when the ink ribbon under use is temporarily unloaded and the same ink ribbon is loaded again, the accumulated value should not be initialized but should be maintained.
However, when the ink ribbon is unloaded/loaded, it is difficult to determine automatically whether or not the ink ribbon is exchanged to a new one in actual practice, and to automatically initialize the accumulated value.
For this reason, this kind of ink exchange time warning apparatus is arranged to display a message requesting an initialization of the accumulated number of printing papers, so that the accumulated value of the number of printing papers may be initialized or maintained in response to a manual operation of the user responsive to the request message. When the ink ribbon is exchanged to a new one, the user is enabled to execute a predetermined reset operation for initialization of the accumulated number of printing paper. On the other hand, when the ink ribbon is temporarily unloaded and loaded again, the user is enabled not to execute the reset operation. Thus, so long as a notice of handling the ink exchange time warning apparatus is determined and the user observes such a notice, the above ink exchange time warning apparatus can function normally.
It is, however, troublesome for the user, particularly to the user who unloads and loads the ink ribbon frequently, to instruct manually the initialization or maintenance of the accumulated number of printing papers at every ink ribbon maintenance process. It is also possible that the user may execute the reset operation erroneously in response to the request message display, although the initialization should not be executed because of loading of the same ink ribbon. Thus the ink exchange time warning apparatus cannot warn the user of the ink exchange time correctly. In particular, even when the user notices the operation error later, the ink exchange time warning apparatus is disabled to function normally.